<?php
   require_once("DButil.php");
//    课程
   $sql="select courseName name,count(1) value from t_course t1 left join t_video t2 on t1.courseId=t2.courseId group by courseName";
   $arr=query($sql);//多条结果
   header("Content-Type:application/json;charset=utf-8");
   echo json_encode($arr);

?>